I read this in the morning and didn't follow to the website. I like it overall it's a neat silent heat option for an office space or something. A larger design with the ability to heat rooms would be neat to see. The price is a killer for most though like Phil mentioned - 1800 USD is what I assume it was saying.
When it comes to being a heater - the efficiency doesn't really matter. Keeping the noise down is the biggest concern. A power hungry beast just allows more heat into the room, if you can downclock it through settings then it can be tweaked to comfort. That's they type of model I would want to see, a 5 month heater (depending on location) with the added benefit of mining BTC.